The Eastern Grey Kangaroo is grey in colour on the top, with a slightly lighter lower body and underside of their very long tail.They have generally small heads, and rather large ears. They can grow to be 7 feet tall, and weigh as much as 54 kgs. They aregrazing animals.
Taxonomy:
Kingdom
Anamalia
Phylum
Chordata
Class
Mammalia
Order
Diprodontia
Family
Macropodidae
Genus
Macropus
Species
Eastern Grey
Habitat
Eastern Greys in their natural habitat
The Eastern Grey is endemic to Australia like other animals such as the Platypus. It is the most commonly spotted species of Kangaroo due to its amazing adaptability.
Eastern Greys inhabit grasslands, woodlands, mountain forests, sub-tropical forests, coastal areas and inland scrubs. They tend to choose land with areas of bush for shelter during the day, and ventures out to graze on nearby pastures of green grass in the night. Eastern Grey Kangaroos live in areas that tend to have more than 250 mm of average annual rainfall.
The Eastern Grey Kangaroos population has increased since European settlement due to the improvement in pasture, and the better provision of watering points for stock.
They can be found inhabiting the Eastern states of Australia, including Tasmania. (See Figure 1).
Mobs of Kangaroos travel long distances. They can easily get their way past man made barriers such as fences.
Figure 1: Eastern Grey Kangaroo Habitat (Red)
Adaptations
The Eastern Grey Kangaroos adaptations help them survive in the environment that they live in.
Labelled by Samantha Banfield
Behavioural Adaptation 1:
When danger is near
If Kangaroos sense danger, they use their hind legs to thump the ground, sending a warning to the rest of their mob. This warning lets the mob know that danger is near. This behaviour could save the lives of the other kangaroos in the mob or even the kangaroo initiating the signal. The other kangaroos could come and help the kangaroo that signaled danger, or depending on the situation, the thumping could enable enough time for the mob to safely get away before the predator or whatever the danger was could do them any harm. This adaptation has probably risen to ensure safety.
Behavioural Adaptation 2:
Mating Habits
The Female Grey Kangaroo can come into season year round. However, it is more common for her to give birth during the Summer time.
Male kangaroos check to see if the female is ready for breeding by sniffing the area around the base of her tail and/or by smelling her urine. If the male sense that the female is receptive to breeding he will follow her around and stroke and grasp her tail. The male aloud to breed with the selected female is the dominant male of the mob.
The female's gestation period is fairly short, just over a month with the joey born just 36 days after mating. The female licks her pouch clean in order to prepare for the arrival of the newborn and leans up against a tree, resting her hindquarters on her tail behind her.
Structural Adaptation 1:
Their ability to hop
Kangaroos have very large tendons in their hind legs that can stretch easily. Due to how muscular their hind legs are, they are very well-suited for hopping. The Kangaroos ability to hop is their first line of defense. The Eastern Grey Kangaroo is able to hop an amazing distance. They have been seen to leap over fences or cars and their leaps have been reported to have reached lengths of 26 feet. Even 10 feet in height! They can also travel at a speed of up to 54 km/h.
Their ability to travel quickly, enables the kangaroos to get away from their predators. Kangaroos don't have many predators , but they are hunted by humans and dingos and some eagles take their chances on young joeys. Overtime, the kangaroos developed their speed in order to increase their chance of survival in situations where they were at risk from predators.
Structural Adaptation 2:
Their tail
The Eastern Grey Kangaroo's tail is 4 ft (1.2 m) in length and is very strong. It is used for balance while running fast and as a prop while standing upright. Male Kangaroos rely on their tails to help them keep their balance when they are boxing. The Kangaroos tail has developed over time to ensure speedy traveling and to help them with balance. In the video below, you will see how kangaroos use their tales whilst fighting each other.
Physiological Adaptation 1:
Diapause
Diapause takes place in female kangaroos. The female kangaroo is almost permanently pregnant. However, that being said, she has the ability to freeze the development of an embryo until her previous joey is able to leave the pouch. The embryo is maintained in a state of inactivity, and as a result the kangaroos normal gestation period is extended (up to a year).
Diapause takes place when the animal does not want to risk their lives during
A female Eastern Grey and two joeys
environmental conditions such as drought, or ifthere is not enough food available to feed their newborn. Delaying the birth gives the mother kangaroo a chance to have ideal conditions to ensure that her offspring can survive when it is born. She can also focus on the joey in her pouch.
There are two types of embryonic diapause; facultative diapause, and obligate diapause. Facultative diapause is more linked to metabolic stress, whereas obligate diapause focusses more on suspending the birth to offer more favourable environmental conditions.
Little is known about what actually causes a Kangaroo to go into diapause, or what it is that keeps the embryo dormant. But diapause is a fascinating event that helps the mother kangaroos ensure her offspring's survival by giving her the opportunity to find better living/food conditions for herself and the joey.
The Eastern Grey Kangaroo
Macropus giganteus
The Eastern Grey Kangaroo is grey in colour on the top, with a slightly lighter lower body and underside of their very long tail.They have generally small heads, and rather large ears. They can grow to be 7 feet tall, and weigh as much as 54 kgs. They aregrazing animals.
Taxonomy:
Habitat
Eastern Greys inhabit grasslands, woodlands, mountain forests, sub-tropical forests, coastal areas and inland scrubs. They tend to choose land with areas of bush for shelter during the day, and ventures out to graze on nearby pastures of green grass in the night. Eastern Grey Kangaroos live in areas that tend to have more than 250 mm of average annual rainfall.
The Eastern Grey Kangaroos population has increased since European settlement due to the improvement in pasture, and the better provision of watering points for stock.
They can be found inhabiting the Eastern states of Australia, including Tasmania. (See Figure 1).
Mobs of Kangaroos travel long distances. They can easily get their way past man made barriers such as fences.
Adaptations
The Eastern Grey Kangaroos adaptations help them survive in the environment that they live in.
Behavioural Adaptation 1:
When danger is near
If Kangaroos sense danger, they use their hind legs to thump the ground, sending a warning to the rest of their mob. This warning lets the mob know that danger is near. This behaviour could save the lives of the other kangaroos in the mob or even the kangaroo initiating the signal. The other kangaroos could come and help the kangaroo that signaled danger, or depending on the situation, the thumping could enable enough time for the mob to safely get away before the predator or whatever the danger was could do them any harm. This adaptation has probably risen to ensure safety.
Behavioural Adaptation 2:
Mating Habits
The Female Grey Kangaroo can come into season year round. However, it is more common for her to give birth during the Summer time.
Male kangaroos check to see if the female is ready for breeding by sniffing the area around the base of her tail and/or by smelling her urine. If the male sense that the female is receptive to breeding he will follow her around and stroke and grasp her tail. The male aloud to breed with the selected female is the dominant male of the mob.
The female's gestation period is fairly short, just over a month with the joey born just 36 days after mating. The female licks her pouch clean in order to prepare for the arrival of the newborn and leans up against a tree, resting her hindquarters on her tail behind her.
Structural Adaptation 1:
Their ability to hop
Kangaroos have very large tendons in their hind legs that can stretch easily. Due to how muscular their hind legs are, they are very well-suited for hopping. The Kangaroos ability to hop is their first line of defense. The Eastern Grey Kangaroo is able to hop an amazing distance. They have been seen to leap over fences or cars and their leaps have been reported to have reached lengths of 26 feet. Even 10 feet in height! They can also travel at a speed of up to 54 km/h.
Their ability to travel quickly, enables the kangaroos to get away from their predators. Kangaroos don't have many predators , but they are hunted by humans and dingos and some eagles take their chances on young joeys. Overtime, the kangaroos developed their speed in order to increase their chance of survival in situations where they were at risk from predators.
Structural Adaptation 2:
Their tail
The Eastern Grey Kangaroo's tail is 4 ft (1.2 m) in length and is very strong. It is used for balance while running fast and as a prop while standing upright. Male Kangaroos rely on their tails to help them keep their balance when they are boxing. The Kangaroos tail has developed over time to ensure speedy traveling and to help them with balance. In the video below, you will see how kangaroos use their tales whilst fighting each other.
Physiological Adaptation 1:
Diapause
Diapause takes place in female kangaroos. The female kangaroo is almost permanently pregnant. However, that being said, she has the ability to freeze the development of an embryo until her previous joey is able to leave the pouch. The embryo is maintained in a state of inactivity, and as a result the kangaroos normal gestation period is extended (up to a year).
Diapause takes place when the animal does not want to risk their lives during
There are two types of embryonic diapause; facultative diapause, and obligate diapause. Facultative diapause is more linked to metabolic stress, whereas obligate diapause focusses more on suspending the birth to offer more favourable environmental conditions.
Little is known about what actually causes a Kangaroo to go into diapause, or what it is that keeps the embryo dormant. But diapause is a fascinating event that helps the mother kangaroos ensure her offspring's survival by giving her the opportunity to find better living/food conditions for herself and the joey.
Resources
Information:
Anderson's Creek Primary School. no date. Eastern Grey Kangaroo. Retrieved July 10, 2010, from http://teachit.acreekps.vic.edu.au/animals/easterngreykangaroo.htm
Billabong Sanctuary. no date. Aussie Animals. Retrieved July 18, 2010, from http://www.billabongsanctuary.com.au/aussie_animals/eastern_grey_roo.html
Eastern Grey Kangaroo. no date. Retrieved July 12, 2010, from http://www.angelfire.com/mo2/animals1/kangaroo/eastgrey.html
Exploring Nature Educational Resource. (2010). Kangaroo. Retrieved July 15, 2010, from http://www.exploringnature.org/db/detail.php?dbID=43&detID=966
Kangaroo Facts. (2010). Kangaroo information, facts and kangaroo figures. Retrieved July 12, 2010, from http://www.giftlog.com/pictures/kangaroo_facts.htm
Pool, W. E. 1982. Mammalian Species. The American Society of Mammalogists. Retrieved July 19, 2010 from http://www.scribd.com/doc/33875163/Eastern-Grey-Kangaroo
rootourism. (2008). Fact Sheet - The Eastern Grey Kangaroo (Mainland). Retrieved June 12, 2010 from http://www.rootourism.com/fsheet23.htm
Wikipedia. (2010). Eastern Grey Kangaroo. Retrieved June 4, 2010 from http://en.wikipedia.org/wiki/Eastern_Grey_Kangaroo
Wikipedia. (2010). Embryonic Diapause. Retrieved July 16, 2010, from http://en.wikipedia.org/wiki/Embryonic_diapause#Facultative_diapause
Images:
An Eastern Grey Kangaroo -
Wikipedia. Eastern Grey Kangaroo. Retrieved July, 2010, from http://en.wikipedia.org/wiki/Eastern_Grey_Kangaroo
Eastern Greys in their natural habitat -
Wikipedia. Eastern Grey Kangaroo. Retrieved July, 2010, from http://en.wikipedia.org/wiki/Eastern_Grey_Kangaroo
Figure 1: Eastern Grey Kangaroo Habitat (Red) -
Anderson's Creek Primary School. no date. Eastern Grey Kangaroo. Retrieved July, 2010, from http://teachit.acreekps.vic.edu.au/animals/easterngreykangaroo.htm
Labelled by Samantha Banfield -
Exploring Nature Educational Resource. (2010). Kangaroo. Retrieved July, 2010, from http://www.exploringnature.org/db/detail.php?dbID=43&detID=966
A female Eastern Grey and two joeys -
Wikipedia. Eastern Grey Kangaroo. Retrieved July, 2010, from http://en.wikipedia.org/wiki/Eastern_Grey_Kangaroo
Video:
Youtube. (2007). Nat Geo Wild: Kangaroo vs Dingo. Retrieved July, 2010, from http://www.youtube.com/watch?v=fMYLXcHI0Sk&feature=player_embedded#!